1.1
We have learned that all computers have similar capabilities and perform essentially the same functions, although some might be faster than others. We have also learned that a computer system has input, output, storage, and processing components; that the processor is the “intelligence” of a computer system; and that a single computer system may have several processors. We have discussed how data are represented inside a computer system in electronic states called bits. We are now ready to expose the inner workings of the nucleus of the computer system — the processor.
我们已经知道，所有的计算机都具有相似的能力，并且在本质上执行相同的功能，尽管一些可能会比另一些快一点。我们也知道，一个计算机系统具有输入，输出，存储和处理部件；处理器是一个计算机系统智能核心，并且一个计算机系统可以有许多个处理器。我们已经讨论过如何在计算机系统内部，用被称作“位”的电子状态来表现数据，现在我们要弄明白计算机系统的核心，即处理器，的内在的工作方式。
The internal operation of a computer is interesting, but there really is no mystery to it. The mystery is in the minds of those who listen to hearsay and believe science-fiction writer. The computer is a nonthinking electronic device that has to be plugged into an electrical power source, just like a toaster or a lamp. 计算机的内部操作很有意思，但确实没有什么神秘可言。所谓的神秘只是存在于那些听信传闻和相信科幻小说作家的人的意识中。计算机就是一种没有思想的需要接通电源的电子设备而已，与烤面包机和台灯差不多。
Literally hundreds of different types of computers are marketed by scores of manufacturers [1]. The complexity of each type may vary considerably, but in the end each processor, sometimes called the central processing unit or CPU, has only two fundamental sections: the control unit and the arithmetic and logic unit. Primary storage also plays an integral part in the internal operation of a processor. These three — primary storage, the control unit, and the arithmetic and logic unit —work together. Let’s look at their functions and the relationships between them.不加夸张地讲，市场上有几百种不同类型的计算机在销售.每种电脑在复杂性上可能有很大区别，但归根结底,每种处理器，有时称为中央处理器即cpu，只有两个基本部分:控制单元和计算逻辑单元.主内存在处理器内部操作中也是一个不可缺少的部分.这三个部件--主内存，控制单元和计算逻辑单元--一起工作.然我们看看它们(各自的)功能和它们之间的联系。
Unlike magnetic secondary storage devices, such as tape and disk, primary storage has no moving parts. With no mechanical movement, data can be accessed from primary storage at electronic speeds, or close to the speed of light. Most of today’s computers use DRAM (Dynamic Random-Access Memory) technology for primary storage.
A state-of-the-art DRAM chip about one eighth the size of a postage stamp can store about 256,000,000 bits, or over 25,600,000 characters of data!
主存与其他的辅助存储器（如：磁带、硬盘）不一样的是，主存不含有运转部件。由于没有机械运转的需要，主存种数据访问可以达到电子的速度，或接近于光速。当今计算机的主存大多数使用DRAM（动态随机存取存储器）技术。目前最新的工艺水平是：一块只有大约1/8张邮票大小的DRAM芯片却可以存储大约256,000,000位，约25,6000,000个字符的数据。
Primary storage, or main memory, provides the processor with temporary storage for programs and data. All programs and data must be transferred to primary storage from an input device (such as a VDT) or from secondary storage (such as a disk) before programs can be executed or data can be processed. Primary storage space is always at a premium; therefore, after a program has been executed, the storage space it occupied is reallocated to another program awaiting execution.
主存储器，也就是说内存，用于为处理器暂时存放程序和数据。所有的程序和数据在被操作之前必须从输入设备（如VDT）或者辅助存储器转存到主存储器中。主存储器存储容量通常是相当有限的，因此，在一个程序执行结束，它所占用的存储空间必须被重新分配给其它正在等待执行操作的程序。
Figure 1-1 illustrates how all input/output (I/O) is “read to” or “written from” primary storage. In the figure, an inquiry (input) is made on a VDT. The inquiry, in the form of a message, is routed to primary storage over a channel (such as a coaxial cable). The message is interpreted, and the processor initiates action to retrieve the appropriate program and data from secondary storage [3].The program and data are “loaded”, or moves, to primary storage from secondary storage. This is a nondestructive read process. That is, the program and data that are read reside in both primary storage (temporarily) and secondary storage (permanently). The data are manipulated according to program instructions, and a report is written from primary storage to a printer.
图 1-1描述了输入/输出设备与主存储器间的读和写过程。在图中，VDT发出一个输入请求，请求是以消息模式通过通道（如同轴电缆）发送到主存储器。这个查询被解释，处理器发起操作从辅助存储器中调用合适的程序和数据。程序和数据从辅助存储器传送到主存储器中，这是一个非破坏性的读取过程，也就是说，程序和数据同时存在于主存（临时保存）和辅助存储器（永久保存）中。根据程序指令的指示，处理器对数据进行操作，并从主存传送一份报告到打印机。
A program instruction or a piece of data is stored in a specific primary storage location called an address. Addresses permit program instructions and data to be located, accessed, and processed. The content of each address is constantly changing as different programs are executed and new data are processed.
程序指令和数据是存储在主存中一个特殊的位置，称为地址空间。通过地址空间可以实现计算机对程序指令和数据的定位、访问和处理。地址空间的内容是经常变化的，这是由于计算机一直在执行不同的程序和数据。
Another name for primary storage is random-access memory, or RAM. A special type of primary storage, called read-only memory (ROM), cannot be altered by the programmer. The contents of ROM are “hard-wired” (designed into the logic of the memory chip) by the manufacturer and can be “read only”. When you turn on a microcomputer system, a program in ROM automatically readies the computer system for use. Then the ROM program produces the initial display screen prompt.
主存储器也称为随机存取存储器，或RAM。还有一种特殊的主存储器，称为只读存储器（ROM），这种存储器不能被程序更改存放的内容。ROM的内容是被生产商通过硬件电路写入的，并且不能被重写。当你启动计算机，ROM中的一个程序会自动就绪等待计算机系统的调用，然后在显示器中显示开机提示。
A variation of ROM is programmable read-only memory (PROM). PROM is ROM into which you, the user, can load “read-only” programs and data. Once a program is loaded to PROM, it is seldom, if ever, changed [4]. However, if you need to be able to revise the contents of PROM, there is EPROM, erasable PROM. Before a write operation, all the storage cells must be erased to the same initial state.
可编程只读存储器（PROM）是另一种ROM，它可以载入只读的程序和数据，一旦载入，将不再改变。然而，若果你需要去修正PROM的内容，可以使用可擦可编程只读存储器。EPROM 在进行一次写操作之前，所有的存储单元必须被还原为同一初始状态。
A more attractive form of read-mostly memory is electrically erasable programmable read-only memory (EEPROM). It can be written into at any time without erasing prior contents; only the byte or bytes addressed are updated.
一种更吸引人的可改写只读存储器是电可擦除可编程只读存储器 (EEPROM)。它可以在任何时候写入，而且不会擦除以前的内容；只会更新被寻址的字节。
The EEPROM combines the advantage of nonvolatility with the flexibility of being updatable in place [6], using ordinary bus control, address, and data lines.
电可擦可编程存储器把非易失性优点和可更新、需要更新的地方的灵活性结合起来，修改时使用普通的总线控制线、地址线和数据线。
Another form of semiconductor memory is flash memory (so named because of the speed). Flash memory is intermediate between EPROM and EEPROM in both cost and functionality. Like EEPROM, flash memory uses an electrical erasing technology. An entire flash memory can be erased in one or a few seconds, which is much faster than EPROM. In addition, it is possible to erase just blocks of memory rather than an entire chip. However, flash memory does not provide byte-level erasure [7]. Like EPROM, flash memory uses only one transistor per bit, and so achieves the high density of EPROM. 另一种半导体记忆体是闪存（意味着速度快）。闪存在性价比上处于EPROM和EEPROM之间，它使用电擦写技术。整个闪存的内容可以在一到几秒内被清除，这是远快于EPROM的。另外，它还可以对部分记忆块而不是整个存储器进行清除。然而，闪存并不提供字节级的擦除。像EPROM，闪存只使用一个晶体管每比特，因此可以实现高密度的EPROM。
Cache Memory
Program and data are loaded to RAM from secondary storage because the time required to access a program instruction or piece of data from RAM is significantly less than from secondary storage. Thousands of instructions or pieces of data can be accessed from RAM in the time it would take to access a single piece of data from disk storage [8]. RAM is essentially a high-speed holding area for data and programs. In fact, nothing really happens in a computer system until the program instructions and data are moved to the processor. This transfer of instructions and data to the processor can be time-consuming, even at microsecond speeds. To facilitate an even faster transfer of instructions and data to the processor, most computers are designed with cache memory. Cache memory is employed by computer designers to increase the computer system throughput (the rate at which work is performed).
程序和数据从辅助存储器装载到RAM中是因为对RAM中的程序指令和数据的访问时间要明显的少于从辅助存储器访问。数以千条的指令和数据能被访问而只需花费从硬盘访问一次数据的时间。RAM是数据和程序的重要的高速存放区，事实上，计算机系统不会进行任何操作直
到程序指令被传入处理器进行执行，这种指令和数据的传输是需要花费时间的，即使传输速度已经是以纳秒来计算了。为了能更快速的传输指令和数据，大多数计算机设计使用高速缓存。计算机设计者使用高速缓存来提高计算机系统的总处理能力（工作效率）。
Like RAM, cache is a high-speed holding area for program instructions and data. However, cache memory uses SRAM (Static RAM) technology that is about 10 times faster than RAM and about 100 times more expensive. With only a fraction of the capacity of RAM, cache memory holds only those instructions and data that are likely to be needed next by the processor. Two types of cache memory appear widely in computers. The first is referred to as internal cache and is built into the CPU chip. The second, external cache, is located on chips placed close to the CPU chip. A computer can have several different levels of cache memory. Level 1 cache is virtually always built into the chip. Level 2 cache used to be external cache but is now typically also built into the CPU like level 1 cache.
和RAM一样，高速缓存也是程序指令和数据的高速存储区。然而，高速缓存使用静态RAM 技术，这种技术比RAM在速度上要高出10倍，价格上高出100倍。cache只保存内存中那一小部分最有可能被处理器执行的指令和数据。两种类型的cache广泛应用于计算机，第一种被植入cpu中的叫做内部高速存储，第二种是外部高速存储，它位于那些靠近cpu的芯片中。一台计算机可以拥有几个不同级别的高速缓存。一级缓存实际上总是植入芯片中，二级缓存过去常常作为外部高速缓存，但是现在也像一级缓存植入cpu内部。
英译汉几个常见问题如下： 1）英译汉时语言组织不符合中文的讲话习惯。在不改变原文绝大部分意思的情况下，不需要字对字或者严格遵守英语语序，在获得原句含意后务必采用中文的思维将译文写出。要求是在读着看过译文后，不能让读着感觉到文章是翻译而得的，即不能留有丝毫翻译的痕迹。 2）英译汉时译文上下文的用词不一致。尤其是学术文献或论文的翻译，除了学术用语和专业用语需要准确，更重要的是全文上下文中同一个词或者短句翻译出的用词或短语必须一致。例如一开始将control panel翻译为“控制面板”，那么全文都不得改变这个译法。 3）英译汉时用词过于口语化。除了剧本，台词，字幕等需要口语化用词的翻译稿件以外。其余大部分翻译，例如文献，论文，合同，申请书，标书等，用词尽量书面化。例如“weight”在统计学和分析学中不可翻译为“给予数值”，必须翻译为“赋权”，两者意思相近，但是采用后者。 4）英译汉时词汇含意理解产生偏差。这是死记单词造成的后果。翻译中，在无上下文的情况下，除非是专有学术名词（例“diabetes”基本上永远都是糖尿病的意思），其余的单词很难说究竟是什么意思，我们只能说某个词大概是对照中文某个词的感觉，但是决不可死认一个意思，死认单词意思造成翻译不通、翻译错误等。当然也不能糊译，不能为了使句子翻译通顺而胡编一个意思。 5）英译汉时英语长句中的意群划分有误。原版的英语资料中长句较多，往往40-50个词之间没有一个标点，修饰成分和意群划分的错误会导致理解错误和翻译错误。原则上，英语中的各类从句，特别是状语从句在句子中的位置相对灵活，没搞明白其修饰对象就会错译。 汉译英几个常见问题如下： 1）汉译英时字对字翻译。这是翻译中最致命的错误，很多人以为认识对应的英语单词或者知道对应的英语单词，这句话才会翻译。其实不是，原则上四千词汇量就能解释大部分英语单词的含义，只不过大部分人不知道如何用简单词汇造句去描述或解释高难度单词。 2）汉译英时中式语序。何谓中式语序，即以“主+谓+宾”为主的句型。这种句子写多了，一旦遇上长句或者语法功能上缺少成分的句子就懵了。所以必须多读，多了解原版英语的句子是如何写的。 3）汉译英时短句太多。这里并不是指写英语短句不好，在考试中建议写短句，这是为了避免语法错误，当然也不要太短了。在较为正式的或专业性强的文本中，汉译英在必要时需要翻译成长句。例如不久前的某论文中的一句：筛选出对靶基因干扰效率最高的 HER2-shRNA慢病毒表达载体并成功包装成病毒去感染SKOV-3细胞而后在体外进行实验的结果显示Her2/neu的siRNA慢病毒载体可以显著抑制靶基因的表达并使卵巢癌SKOV3细胞的生物学行为明显受抑。因此，熟练掌握各类从句的写法和作用很重要。 4）汉译英时英语词汇词义辨析不清而导致误用，用词不准。大部分人的翻译习惯是，凡是中文有英文的对应单词，就二话不说直接用，其实这个是不对的。很多同义词意思相近，用法和所用的语境场合完全不同。例如“base”“basis”“foundation”，意思几乎相同，但是用法完全不同。尤其是学术文章，误用就导致歧义。 5）汉译英时逻辑混乱结构不清。汉译英中的逻辑和语句结构相当重要。逻辑混乱，即译文毫无章法，思绪混沌，不知所云。结构不清，即英语的从句或其他成分在句中的位置胡乱摆放，进行翻译的人员自然是清楚的指导这些英语句子的含义，因为是看着中文翻译过来的，想不知道中文含义都难，但是没看过中文的读着就会因此而看得云里雾里，从而导致读者难以理解译文。
Chapter 1 Passage 1 Human Body In this passage you will learn: 1. Classification of organ systems 2. Structure and function of each organ system 3. Associated medical terms To understand the human body it is necessary to understand how its parts are put together and how they function. The study of the body's structure is called anatomy; the study of the body's function is known as physiology. Other studies of human body include biology, cytology, embryology, histology, endocrinology, hematology, immunology, psychology etc. 了解人体各部分的组成及其功能，对于认识人体是必需的。研究人体结构的科学叫解剖学；研究人体功能的科学叫生理学。其他研究人体的科学包括生物学、细胞学、胚胎学、组织学、内分泌学、血液学、遗传学、免疫学、心理学等等。 Anatomists find it useful to divide the human body into ten systems, that is, the skeletal system, the muscular system, the circulatory system, the respiratory system, the digestive system, the urinary system, the endocrine system, the nervous system, the reproductive system and the skin. The principal parts of each of these systems are described in this article. 解剖学家发现把整个人体分成骨骼、肌肉、循环、呼吸、消化、泌尿、内分泌、神经、生殖系统以及感觉器官的做法是很有帮助的。本文描绘并阐述了各系统的主要部分。 The skeletal system is made of bones, joints between bones, and cartilage. Its function is to provide support and protection for the soft tissues and the organs of the body and to provide points of attachment for the muscles that move the body. There are 206 bones in the human skeleton. They have various shapes - long, short, cube - shaped, flat, and irregular. Many of the long bones have an interior space that is filled with bone marrow, where blood cells are made. 骨骼系统由骨、关节以及软骨组成。它对软组织及人体器官起到支持和保护作用，并牵动骨胳肌，引起各种运动。人体有206根骨头。骨形态不一，有长的、短、立方的、扁的及不规则的。许多长骨里有一个内层间隙，里面充填着骨髓，这即是血细胞的制造场所。 A joint is where bones are joined together. The connection can be so close that no movement is possible, as is the case in the skull. Other kinds of joints permit movement: either back and forth in one plane - as with the hinge joint of the elbow - or movement around a single axis - as with the pivot joint that permits the head to rotate. A wide range of movement is possible when the ball - shaped end of one bone fits into a socket at the end of another bone, as they do in the shoulder and hip joints. 关节把骨与骨连接起来。颅骨不能运动，是由于骨与骨之间的连接太紧密。但其它的关节可允许活动，如一个平面上的前后屈伸运动，如肘关节；或是绕轴心旋转运动，如枢轴点允许头部转动。如果一根骨的球形末端插入另一根骨的臼槽里，大辐度的运动（如肩关节、髋关节）即成为可能。 Cartilage is a more flexible material than bone. It serves as a protective, cushioning layer where bones come together. It also connects the ribs to the breastbone and provides a structural base for the nose and the external ear. An infant's skeleton is made of cartilage that is gradually replaced by bone as the infant grows into an adult. 软骨是一种比一般骨更具韧性的物质。它是骨连结的保护、缓冲层。它把肋骨与胸骨连结起来，也是鼻腔与内耳的结构基础。一个婴儿的骨骼就是由软骨组成，然后不断生长、
1) Electricity can be measured in amount and quality. 电可以用数量和质量来度量。 2) Instrument transformers are installed on the high-voltage equipment. 互感器安装在高压设备上。 3) Electric power is generated in power generating stations or plants. 电能是在发电站或发电厂产生的。 4) The meters are calibrated and the scale is designed to read the value of the desired unit. 这些仪表可以被校准并且设计了不同的量程，以便读出期望的数值。 5)Electrical energy can be stored in two metal plates separated by an insulation medium. Such a device is called a capacitor, and its ability to store electrical energy is termed capacitance. It is measured in Farads. 电能可以储存在被一绝缘介质隔开的两块金属板中，这样的装置被称为电容器，它储存电能的能力就被称为电容。电容的测量单位是法拉。 1)The signal should be filtered before it is amplified. The signal should be filtered before being amplified. 放大信号前，应先对其进行滤波。 2)An object becomes hot. It is placed in the sun. Once being placed in the sun, an object becomes hot. 物体放置在太阳下会变热。 3)We must do various experiments before a new electronic product is designed. Before designing a new electronic product we must do various experiments. 在设计一个新的电子产品之前，我们必须做各种实验。 4)Changing resistance is a method for controlling the flow of the current. 改变电阻是控制电流的一种方法。 5)Conducting electricity means the flow of electrons through an object. 传导电流意味着电子在物体内的流动。 1)The power supply, which is shown in block-diagram in Fig.1, is a single-phase switch-mode inverter. The power supply shown in block-diagram in Fig.1 is a single-phase switch-mode inverter. 图1中用框图表示的电源是一个单相开关逆变器。 2)A three-phase circuit, as it was pointed out above, is merely a combination of three single-phase circuits. A three-phase circuit, as pointed out above, is merely a combination of three single-phase circuits. 正如上面所指出的那样，三相电路只不过是三个单相电路的组合。 3) The transistor, which is working with correctly polarities, can work as an amplifier. The transistor working with correctly polarities can work as an amplifier. 工作于正确电源极性下的晶体管，作用就像放大器。 1）The capacity of individual generators is larger and larger so that the increasing demand of electric power is satisfied. The capacity of individual generators is larger and larger to satisfy the increasing demand of electric power. 单台发电机的容量越来越大，目的就是满足不断增长的用电需求。 2) What does a fuse do? It protects a circuit. The function of a fuse is to protect a circuit. 保险的作用就是保护电路。
第一单元 1.They took advantage of our helpless situation and took over our company. 2.Although there are still difficulties ahead of us. I am sure that we Chinese people will have the wisdom to bring about the peaceful unification of our country on our own. 3.It is wrong to emphasize nothing but GDP. It will give rise to many serious problems. 4.He loves to show off his wealth, but that is all in vain. People still avoid him as though he were poison. 5 He soon fell in love with the village and decided to make it a beautiful garden together with other villagers 6.We must spend more money in fighting against global warming. Besides, we must resort to tough laws. It is not just a matter of money. 7.When the police reached the school, the students and teachers were still in a daze. 8.This corrupt official was still clinging to his power. He refused to step aside. 9.When the man finally came into view, I found it was my father. I didn’t know how he managed to find this place in the heavy snow. At that moment, I burst into tears.
第二部分 控制理论 第1章 1.1控制系统的引入 人类控制自然力量的设计促进人类历史的发展,我们已经广泛的能利用这种量进行在人类本身力量之外的物理进程?在充满活力的20世纪中,控制系统工程的发展已经使得很多梦想成为了现实?控制系统工程队我们取得的成就贡献巨大?回首过去,控制系统工程主要的贡献在机器人,航天驾驶系统包括成功的实现航天器的软着陆,航空飞机自动驾驶与自动控制,船舶与潜水艇控制系统,水翼船?气垫船?高速铁路自动控制系统,现代铁路控制系统? 以上这些类型的控制控制系统和日常生活联系紧密,控制系统是一系列相关的原件在系统运行的基础上相互关联的构成的,此外控制系统存在无人状态下的运行,如飞机自控驾驶,汽车的巡航控制系统?对于控制系统,特别是工业控制系统,我们通常面对的是一系列的器件,自动控制是一个复合型的学科?控制工程师的工作需要具有力学,电子学,机械电子,流体力学,结构学,无料的各方面的知识?计算机在控制策略的执行中具有广泛的应用,并且控制工程的需求带动了信息技术的与软件工程的发展? 通常控制系统的范畴包括开环控制系统与闭环控制系统,两种系统的区别在于是否在系统中加入了闭环反馈装置? 开环控制系统 开环控制系统控制硬件形式很简单,图2.1描述了一个单容液位控制系统, 图2.1单容液位控制系统 我们的控制目标是保持容器的液位h 在水流出流量V 1变化的情况下保持在一定 可接受的范围内,可以通过调节入口流量V 2实现?这个系统不是精确的系统,本系 统无法精确地检测输出流量V 2,输入流量V 1以及容器液位高度?图2.2描述了这 个系统存在的输入(期望的液位)与输出(实际液位)之间的简单关系, 图2.2液位控制系统框图 这种信号流之间的物理关系的描述称为框图?箭头用来描述输入进入系统,以及
1. Civil engineering，the oldest of the engineering specialties，is the planning，design，construction, and management of the built environment．This environment includes all structures built according to scientific principles，from irrigation and drainage systems to rocket-launching facilities. 土木工程，最老的工程专业，是建筑环境的规划、设计、施工和管理。这个环境包括从灌溉和排水系统到火箭发射设施的所有根据科学原理建造的结构物。 2. Civil engineers build roads，bridges，tunnels，dams，harbors，power plants，water and sewage systems，hospitals，schools，mass transit，and other public facilities essential to modern society and large population concentrations． 土木工程师修建道路、桥梁、隧道、大坝、港口、发电站、水系统和污水系统，医院、学校、公共交通系统，以及现代化社会和大量人口集中的地方所必需的其他公共设施。 3. Computers are a necessity for the modern civil engineer because they permit the engineer to efficiently handle the large quantities of data needed in determining the best way to construct a project． 计算机对于现代土木工程师而言是必不可少的，因为它们可使工程师高效地处理大量数据，这些数据是在确定最优施工方案时所需要的。 4. They also determine the combination of appropriate materials：steel，concrete，plastic，stone，asphalt，brick，aluminum，or other construction materials． 他们还确定适当的材料组合：钢材、混凝土、塑料、石料、沥青、砖、铝或其他的建筑材料。 5. In this branch of civil engineering, engineers build pipelines and related facilities which transport liquids, gases, or solids ranging from coal slurries (mixed coal and water) and semiliquid wastes, to water, oil, and various types of highly combustible and noncombustible gases. 在土木工程的这个分支里，工程师修建运输液体、气体或固体的管道和相关的设施，运输的物质范围从煤浆和半液体废料到水、石油和不同类型的高燃性和非燃性气体。 6. They coordinate the activities of virtually everyone engaged in the work：the surveyors；workers who lay out and construct the temporary roads and ramps，excavate for the foundation，build the forms and pour the concrete；and workers who build the steel framework．These engineers also make regular progress reports to the owners of the structure． 事实上，他们协调工程中每个人的活动：勘测员、为临时道路和斜坡定线和施工、挖基础、建模和浇注混凝土的工人、以及绑扎钢筋的工人。这些工程师还为建筑业主定期提供进度报告。 7. This art includes，in addition to buildings，all the civil engineering structures such as dams，canals，tunnels，aqueducts，and bridges．
商务英语写作 商务英语翻译：商务英语五大实用翻译技巧 商务英语是为国际商务活动这一特定的专业学科服务的专门用途英语，所涉及的专业范围很广，并具有独特的语言现象和表现内容、文体复杂。商务英语翻译要求翻译者具备丰富的商务理论和商务实践知识，为了提高翻译质量，翻译者必须具备一定的自身条件。 第一，翻译者的汉语功底要好。很多人往往忽视这一点，认为汉语是自己的母语，凭着自己原来的底子应付翻译中的问题，是绰绰有余的。然而在真正的翻译过程中，为了一个词语或者一个句型，冥思苦想了半天也得不到一个满意的结果。有时好不容易想出来了也觉得不够理想。由此可见，汉语表达能力和对汉语理解能力的大小直接影响翻译的好坏。下功夫学好汉语，打好汉语基础对于翻译是十分重要的。 第二，英语语言能力要强。全面的语法知识和大量的词汇量缺一不可。如果只有大量的词汇量，而没有较好的英语语法知识。翻译过程中译者的理解肯定是错误百出，而且牛头不对马嘴。因此我们要提高在英汉翻译中对于英文句子理解的准确性及汉英翻译中英文表达的准确性。 第三，知识面要广。商务英语翻译中要很好的做到这一点，就
要掌握商务理论和贸易实务等理论知识及贸易实践经验。同时译者还要具有丰富的百科知识，对天文地理、古今中外不说通晓，也要了解其中的一些基本知识。没有一定的常识，译者的语言水平即使再高，也是无法做好翻译工作的。 一、一词多义 同一个词，由于语境不同，其词义可千差万别。试看下面几个例子： 1.They cannot obtain credit at all in the trade. 他们生意信誉已荡然无存。 2.They have opened the covering credit with the Bank of China,London. 他们已从伦敦中国银行开立了有关信用证。 以上两个句子credit 词义都有所区别。 二、词类转译 词类转译是国际商务翻译中常见的译词技巧。常见的有名词与动词、介词与动词的互相转译。 1.名词与动词的互相转译： Before the payment of these tariffs, the imported goods
汉译英专项练习 一、倍数增减的表示法 5 1) Force N1 _______________(比力N2大2.5倍). is 2.5 times greater than Force N2 （考点：倍数+形容词/副词比较级+ than） 2) This substance _______________(反应速度是另外那种物质的三倍). reacts three times as fast as the other one （考点：倍数+ as +形容词/副词+ as） 3) The earth _______________(是月球大小的49倍). is 49 times the size of the moon （考点：倍数+名词） 4) The landlord _______________(想将租金提高三分之一). wants to raise the rent by a third （考点：动词+ by +数词/百分比/倍数） 5) They _______________(计划将投资增加一倍). plan to double their investment （考点：double +名词） 二、时态6 1) Be quick, _______________(否则等我们到达教堂时婚礼就已经结束了). or the wedding will have finished by the time we get to the church （考点：将来完成时） 2) When she got home, _______________(孩子们已经睡着了). the children had fallen asleep （考点：过去完成时） 3) When I prepare for the college entrance examination, _______________(我姐姐将在海边度假). my sister will be taking her vacation at the seaside （考点：将来进行时） 4) I_______________(一上午都在修改我的简历). have been revising my resume all the morning （考点：现在完成进行时） 5) Do you often go on holiday? _______________(不，我已经有五年没有度假了). No. It has been five years since I went on holiday （考点：It has been…since sb. did sth.表示某人有多长时间没有做某事了） 6) He joined the army in October, 2001. _______________(他参军已五年了). He has been in the army for 5 years （考点：1.现在完成时；2.要用持续性动词才能接一段时间） 三、被动语态5 1) The blackboard and chalk _______________(正在被电脑和投影机所取代). is being replaced by the computer and the projector （考点：被动语态的现在进行时） 2) The book _______________(到今年年底就将已出版). will have been published by the end of this year （考点：被动语态的将来完成时）
1、应力和应变 应力和应变的概念可以通过考虑一个棱柱形杆的拉伸这样一个简单的方式来说明。一个棱柱形的杆是一个遍及它的长度方向和直轴都是恒定的横截面。在这个实例中，假设在杆的两端施加有轴向力F，并且在杆上产生了均匀的伸长或者拉紧。 通过在杆上人工分割出一个垂直于其轴的截面mm，我们可以分离出杆的部分作为自由体【如图1(b)】。在左端施加有拉力P，在另一个端有一个代表杆上被移除部分作用在仍然保存的那部分的力。这些力是连续分布在横截面的，类似于静水压力在被淹没表面的连续分布。 力的集度，也就是单位面积上的力，叫做应力，通常是用希腊字母，来表示。假设应力在横截面上是均匀分布的【如图1(b)】，我们可以很容易的看出它的合力等于集度，乘以杆的横截面积A。而且，从图1所示的物体的平衡，我们可以看出它的合力与力P必须的大小相等，方向相反。因此，我们可以得出 等式(1)可以作为棱柱形杆上均匀应力的方程。这个等式表明应力的单位是，力除以面积。当杆被力P拉伸时，如图所示，产生的应力是拉应力，如果力在方向是相反，使杆被压缩，它们就叫做压应力。 使等式(1)成立的一个必要条件是，应力，必须是均匀分布在杆的横截面上。如果轴向力P作用在横截面的形心处，那么这个条件就实现了。当力P没有通过形心时，杆会发生弯曲，这就需要更复杂的分析。目前，我们假设所有的轴向力都是作用在横截面的形心处，除非有相反情况特别说明。同样，除非另有说明，一般也假设物体的质量是忽略的，如我们讨论图1的杆一样。 轴向力使杆产生的全部伸长量，用希腊字母δ表示【如图1(a)】，单位长度的伸长量，或者应变，可以用等式来决定。 L是杆的总长。注意应变ε是一个无量纲的量。只要应变是在杆的长度方向均匀的，应变就可以从等式(2)中准确获得。如果杆
3 Earthquakes Earthquakes is trembling or shaking movement of the Earth’s surface.Most earthquakes are minor https://www.doczj.com/doc/7f14324079.html,rger earthquakes usually begin with slight tremors but rapidly take the form of one or more violent shocks,and end in vibrations of gradually diminishing force called aftershocks.The subterranean point of origin of an earthquake is called its focus;the point on the surface directly above the focus is the epicenter .The magnitude and intensity of an earthquake is determined by the use of scales,e.g.,the Richter scale and Mercalli scale. Most earthquakes are causally related to compressional stress or tensional stress built up at the margins of the huge moving lithospheric plates that make up the Earth’s surface.The immediate cause of most shallow earthquakes is the sudden release of stress along a fault,or fracture in the Earth’s crust resulting in moving of the opposing blocks of rock past one another.These movements cause vibrations to pass through and around the Earth in wave form,just as ripples are generated when a pebble is dropped into water.V olcanic eruption,rockfalls,landslides,and explosions can also cause a quake,but most of these are of only local extent. 6 Evidence from radiometric dating indicates that the Earth is about 4,570 million years old.Geologists have divided Earth’s history into a series of time intervals.These time intervals are not equal in length like the hours in a day.Instead the time intervals are variable in length.Different spans of time on the time scale are usually delimited by major geological or paleontological events,such as varying rock type or fossils within the strata and mass extinctions.For example,the boundary between the Cretaceous period and the Paleogene period is defined by the first appearance of animals with hard parts. The geologic time scale was formulated during 地震 地震颤动或发抖运动的地球表面。大部分地震是轻微地震。大地震通常开始轻微的颤动而迅速采取一个或更猛烈冲击的形式，并最终在逐渐减少振动的力称为余震。地震起源的地下点称为重心；表面上以上的重点是中心点。地震的震级和强度的尺度，确定使用例如，李希特尺度和麦加利震级。 大部分地震是因果关系的压应力或拉应力建立在巨大岩石圈板块的运动，使地球表面的空间。最浅的地震的直接原因是沿断层应力的突然释放，或断裂在地壳导致岩石过去彼此对立块体运动。这些运动引起的振动通过环绕地球以波的形式，就像涟漪时产生一个石子投进水中。火山喷发，崩塌，滑坡，和爆炸也可以引起地震，但这些只是局部性的范围。 证据来自辐射测年表明，地球的年龄大约是4570000000岁。地质学家划分地球历史划分成一系列的时间。这些时间间隔的长度像一天中的时间是不相等的。相反，时间间隔的长度是可变的。时间在时间尺度不同跨度通常是由主要的地质或古生物事件分隔的，如不同的地层和大规模物种灭绝的岩石或化石类型。例如，白垩纪和古近纪是用坚硬的部分动物的第一次出现定义之间的边界。
汉译英 1.广场舞是社区中老年居民以健身、社交等为目的在广场、公园等开敞的地方进行的健身操或舞蹈，通常以高分贝的音乐伴奏。广场舞在中国大陆无论南北皆十分普遍。对于广场舞的确切认识，社会学界及体育界目前均未达成共识。广场舞的高分贝音乐常常造成噪音滋扰，因此许多居民反对在小区中跳广场舞。 The square dancing is a bodybuilding exercise or dance performed in wide and open places such as squares and parks among the middle-aged and old residents in communities, with the purpose of bodybuilding, socializing and so on, generally accompanied with high-pitched music. The square dancing is very popular all over mainland China, whether in the north or in the south. Neither the sociological circle nor the sports circle has currently reached a consensus on the exact perception of the square dancing. The high-pitched music of the square dancing often causes noisy disruption, and therefore many residents are opposed to the square dancing in communities. 2.故宫，又称紫禁城，是明、清两代的皇宫，二十四位皇帝在此生活起居和处理政务。它是世界现存最大、最完整的木质结构的古建筑群(architectural complex)。宫殿墙壁的色调以红色和黄色为主,红色代表快乐、好运和财富，而黄色代表帝王的神圣和尊贵。近十几年来，故宫平均每年接待中外游客600-800万人次，随着旅游业的繁荣，游客人数有增无减，可见人们对故宫的兴趣长盛不衰。 The Imperial Palace, also known as the Forbidden City, was the palace in Ming and Qing Dynasties where 24 emperors lived and handled government affairs. It is the largest and most complete existing ancient wooden architectural complex in the world. The palace wall was painted mainly in red and yellow. Red represents happiness, luck and fortune while yellow symbolizes imperial holiness and dignity. In recent decades, the Imperial Palace is visited annually by six to eight million tourists at home and abroad. Moreover, with flourishing tourism industry, the number of tourists keeps increasing. It shows people’s everlasting and unfading interest in the Imperial Palace. 3.《新闻联播》是中国中央电视台（CCTV）每日播出的一个新闻节目。节目每次播出时长一般为30分钟。它被中国大陆大多数地方频道同时转播，这使得它成为世界上收看人数最多的节目之一。自从1978年1月1日首次播出以来，它就以客观、生动、丰富的纪实手段记录着中华大地每一天的变化。作为中国官方新闻资讯类节目，《新闻联播》以沉稳、庄重的风格著称。 Xinwen Lianbo is a news program broadcast by China Central Television (CCTV) every day. It generally takes 30 minutes every time to broadcast the program. It is relayed simultaneously by most local television channels in the mainland of China, which makes it one of the world’s most-watched programs. Since it was first broadcast on January 1st, 1978, it has been recording the changes of every day throughout China by documentary means that is objective, vivid and rich. As the Chinese official news information program, Xinwen Lianbo is well-known for its